Bottom expander



A. A. HEYMAN BOTTOM EXPANDER July 8, 1958 5 Sheets-Sheet 2 Filed June 14, 1956 N: m& n:

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INVENTOR. ALBERT A.HEYMAN BY wjfil W ATTORNEY July 8, 1958 A. A. HEYMAN 2,842,033

,BOTTOM EXPANDER Filed June 14, 1956 5 Sheets-Sheet 5 FIG.4.

. INVENTOR.

ALBERT A. HEYMAN ATTORNEY July 8, 1958 A. A. HEYMAN ,3

BOTTOM EXPANDER Fil'ed June 14, 1956 5 Sheets-Sheet '4 I INVIENTOR. ALBERT A.HEYMAN ATTORNEY July 8 1958 A. A. HEYMAN 2,842,033

BOTTOM EXPANDER Filed June 14, 1956 5 Sheets-Sheet 5 FIG. 14. FIG.15.

IN V EN TOR.

ALBERT A. HEYMAIN BY I Ma Ham ATTORNEY United States Patent BOTTOM EXPANDER Albert A. Heyman, Baltimore, Md., assignor to The Maryland Cup Company, Baltimore, Md., a corporation of Maryland Application June 14, 1956, Serial No. 591,438

Claims. (Cl. 93-365) This invention relates to machines for making paper cups and it is more particularly concerned with a unit thereof, generally known as a bottom expander.

In the manufacture of the so called fiat bottom paper cups, the operation conventionally includes the positioning of a frustro-conical mandrel at a station for receiving a blank to form the bottom section, then at another station for receiving a blank to form the side wall, and then at subsequent stations for operating upon these two blanks to complete the formation of the cup and discharge it from the machine. Included amount the devices for performing such operations is the bottom expander which is positioned axially of a mandrel station and moved inwardly to apply outward rolling pressure to the bottom annular joint of the cup to properly form it and effect a tight seal between the bottom and side wall blanks, glue having been previously applied.

The general object of the present invention is the provision of an improved mechanical unit for effecting this rolling pressure and it is more particularly an improvement over the device shown in U. S. Patent No. 2,600,355.

In the accompanying drawing there is illustrated an embodiment of this invention in which:

Fig. 1 is a side elevational view of the embodiment in its normal non-operating position relative to the mandrel, apart from the rest of the cup making machine.

Fig. 2 is a view similar to Fig. 1, partly broken away, with the bottom expander. in operating position relative to the mandrel station.

--Fig. 3 is a top plan view of the device in the operating position.

Fig. 4 is a longitudinal sectional view 44 of Fig. 3.

i Fig. 5 is a cross-sectional view along the line 5--5 of Fig. 3.

Fig. 6 is a longitudinal sectional view along the line 6-6 of Fig. 1.

Fig. 7 is a forward end elevationalview of the front section.

Fig. 8 is a bottom plan view of the two base members that are movable relative to each other.

'Fig. 9 is a rear end elevational view of the front section.

Fig. 10 is a front end elevational view of the rear section.

Fig. 11 is a side elevational view showing certain inner working members apart from other members for clarity of illustration.

Fig. 12 is a side elevational view of the eccentric core without the expander roller.

Fig. 13 is a front end elevational view of the eccentric core without the expander roller.

Fig. 14 is a side elevational view of one of the internal parts, partly broken away, hereinafter referred to as the eccentric core barrel.

Fig. 15 is a front end elevational view of the barrel shown in Fig. 14.

along the line 2,842,033 Patented July 8, 1958 Fig. 16 is a front end view of the barrel on a larger scale with the core in place therein and rotated to the position of concentricity for the expander roller shaft bearing.

Fig. 17 is a view similar to Fig. 16 with the relative rotation in the extreme position of eccentricity for the expander roller shaft bearing.

Fig. 18 is a side elevational view of the expander roller and its mounting shaft, apart from the device as a whole.

Fig. 19 is a fragmentary view, partly in section, showing the bottom portion of a cup on a mandrel being operated upon in accordance with the invention.

Fig. 20 is a sectional along the line 20-20 of Fig. 19.

Referring with more particularity to the drawing in which like numerals designate like parts throughout the views shown, the embodiment illustrated comprises two sections, generally designated as the front section A and the rear section B, which are axially aligned and axially movable relative to each other.

The forward section A is carried on a horizontal slide base 31 which is integral with a vertical bearing support 32. The support 32 carries a ball bearing assembly consisting of an inner race 33 and an outer race 34. The ball bearing assembly is disposed in an aperture 35 between a forward flange 36 and a rearward removable retaining ring 37, the latter being held by bolts 38.

The forward end of a barrel member 39 is supported by the inner race 33. The barrel 39 extends rearwardly from the inner race and the bore 40 thereof is eccentric.

of its longitudinal axis. The bore 40 supports a core 41 whichis rotatable in the bore.

The forward end of the core 41 has an eccentric aperture 42, the rearwardmost position 42A of which is threaded to receive the threaded end 44 of a shaft 45 that rotatably carries the expander roller 46.

The eccentricity of the aperture 42 in the core 41 is equal to the eccentricity of the bore 40 of the barrel 39. Consequently, the core 41 may be rotated to a position where the eccentricities compensate each other fully so that the aperture 42 is at its innermost position,

which is the true center of the barrel as shown in Fig.

The shaft 47 is rotatably mounted in an elongated bore 49 of a hollow shaft portion 50 connected to and extending rearwardly from an enlarged forward hollow portion 51 forming a part of the rear section B. The

shaft 47 is also axially movable in said bore 49.

The portion 50 is keyed to a collar 52 secured to the inner races 53, 54 of a pair of ball bearing assemblies 55, 56, separated from the outer races 57, 58 by balls 59, 60, respectively. These ball bearing assemblies are mounted in a bearing support 61 which is integral with the base 62 of the section B. The ball bearing assemblies 55 and 56 are held in spaced apart relation by abutting against opposite sides of an inner ring flange 63 and they are held in these respective positions by holding rings 64 and 65 at the front and rear respectively, removably attached by bolts 66 and 67.

The enlarged forward portion 51 is provided with guide slots 68 and 69 which slidably meshes with corresponding lugs 70 and 71, respectively, held on the periphery of the barrel 39 with screws 72 and 73.

The portion 50 is also provided with a cam groove 74 for theroller 48. The groove 74 extends rearward from the forward end of the portion a short distance and then spirals rearwardly for A of a turn. The groove is just wide enough to accommodate the roller 48 without binding. Accordingly, as the two sections A and B move relative to each other, the action between the roller 4-8 and groove 74 is such as to cause relative rotational displacement between the barrel 39 and the core 41, and hence to change the eccentricity of the expander roller 46.

In actual use, the portion 51, the barrel 39 and core 41 are in constant rotation and the power to rotate them is provided by an electric motor mounted on a platform 76 which forms an integral part of the base 62 of the rearward section B. This motor has a driving gear 77 on a power take-off shaft 78 which meshes with a gear 79 keyed to a shaft extension 80 of the portion 50 and which projects rearwardly therefrom beyond the support member 61.

The shaft extension 80 is hollow and is internally threaded to receive a gauge pin 81 which projects through the extension 80 into the bore 49 of the intermediate portion 50. By adjusting the position of this gauge pin, the rearward limit of movement of the first section A relative to the rear section B can be set and hence provide for the desired throw of eccentricity under any given operating conditions. The adjusted position of the pin 81 can be secured by a back-up nut 82.

The two sections A and B are resiliently held together by bolts 83 and 84 one on either side passing through apertures 85 and 86 in the side lobes 87 and 88 of the support 32 and apertures 89 and 90 in lobes 91 and 92 of the support 61.

Between the corresponding lobes 87 and 91, and the lobes 88 and 92, coil springs 93 and 94, respectively, are disposed about the bolts 83 and 84. These bolts extend rearwardly beyond the lobes 91 and 92 and additional coil springs 95 and 96 are disposed between these lobes and nuts 97 and 98, respectively, on the ends of the bolts.

The main loading spring is a coil spring 99 disposed about the forward hollow enlarged portion 51 between a forward annular flange 100 thereof and a thrust plate 101 on the front of the support 61.

The expander roller 46 is freely rotatable on the mounting shaft 45. It has an enlarged medial portion 102 and a recessed portion 103 forward of the medial portion. The rim 104 of the forward portion is slightly undercut to form a frustro-conical or dovetail annular surface parallel to the inner wall 105 of the bottom annular joint 106 between the bottom blank 107 and the main portion of the cup 108 on a mandrel 109.

A forward plate 110 is secured to the flange 36 on the front of the mounting 32 and it has a tapered aperture 111 to receive the bottom of the cup 108 and mandrel 109, and against which pressure is applied to move the sections A and B relative to each other by the application of a forward force to the section B through a downwardly projecting member. Section A abuts an adjustable stop 111A which prevents the wall of the aperture from pressing too hard on the cup. See Figs. 1 and 2.

As shown in Fig. 2, during the expanding operation, the enlarged medial portion 102 lies flat against the bottom joint 106 of the cup. As pressure is applied forwardly by the rear section B, the eccentricity of the expander roller 46 is, by means of cam follower 112 and cam 113, changed until it is forced against the joint, whereupon a number of revolutions of the expander roller are effective to accomplish the desired result.

Having thus described my invention, I claim:

1. In a bottom expander for paper cups having a forward section and a rearward section movable relative to each other, a barrel carried by the forward section, said barrel having an eccentric bore extending parallel to the direction of relative motion of said sections, a core piece rotatably mounted in said bore, said core having an eccentric aperture parallel to the bore, a shaft mounted in said aperture, and means for rotating the core in the barrel bore when the sections move relative to each other.

2. In a bottom expander for paper cups having a forward section and a rearward section movable relative to each other, a barrel carried by the forward section, said barrel having an eccentric bore extending parallel to the direction of relative motion of said sections, a core member rotatably mounted in said bore, said core having an eccentric aperture parallel to the bore, a first shaft mounted in said aperture, a second shaft connected to and extending rearwardly from said core, means in said rearward section for supporting the second shaft, and means for rotating the second shaft when said sections move relative to each other.

3. In a bottom expander for paper cups having a forward section and a rearward section movable relative to each other, a barrel carried by the forward section, said barrel having an eccentric bore extending parallel to the direction of relative motion of said sections, a core member rotatably mounted in said bore, said core having an eccentric aperture parallel to the bore, a first shaft mounted in said aperture, a second shaft connected to and extending rearwardly from said core, means in said rearward section for supporting the second shaft, a cam follower carried by the second shaft, and a cam track for the cam follower carried by the rearward section to cause the second shaft to rotate when it moves axially relative to the rearward section.

4. The subject matter as defined by claim 3 and means for limiting the axial movement of the second shaft relative to the rearward section.

5. The subject matter as defined by claim 4 in which the limiting means comprises an axially movable member in abutting relation to the second shaft, and means for holding the member in adjusted positions relative to the second shaft.

References Cited in the file of this patent UNITED STATES PATENTS 

